1. Field of the Invention
The present invention relates to a mobile wireless terminal and particularly to mobile wireless terminal such as a cellular phone having a built-in antenna.
2. Description of the Related Art
Conventionally, a cellular phone as a typical mobile wireless terminal frequently uses a whip antenna or fixed coil antenna which can be pulled up or is storable. However, because of recent downsizing of cellular phones and inclusion of antennas inside casings, it is indispensable for design of an antenna to take into consideration design of a casing.
A known method of changing directivity of an antenna of a mobile wireless terminal is a method in which a parasitic element is provided near a feeding part of an antenna element (see JP-A-2003-037413).
In a mobile wireless terminal having a downsized/built-in antenna, the antenna characteristics tend to deteriorate. In addition, the antenna characteristics are easily influenced by human bodies. Problems of deterioration in characteristics, gain loss, and the like hence have arisen. Directivity of an antenna is therefore difficult to improve without sacrificing designs of the outer appearance.